BABBQ5 - Automated Testing for Modern Android Applications

How to use dependency injection, mocking, and a test runner to automate UI & unit testing. Sample app source on GitHub: https://github.com/abdyer/android-test-demo

Transcript

1. AUTOMATED TESTING FOR Modern ANDROID APPLICATIONS
2. ANDY DYER +AndrewDyer || @dammitandy
4. MUSIC LIBRARY
5. WRIST PRESENTER
6. RECORDS, COFFEE & BEER
7. "Ich lerne Deutsch."
8. MAKING ANDROID APPS TESTABLE
9. DYNAMIC LANGUAGES "Tests shouldn't drive implementation."
10. STATIC LANGUAGES "You know nothing."
11. MAKING ANDROID APPS TESTABLE ▸ Dependency injection ▸ Mocking & stubbing ▸ Unit & integration tests
12. DEPENDENCY INJECTION
13. DEPENDENCY INJECTION ▸ Decouples application components ▸ Classes receive dependencies, don’t have to know where to find them or how to create them ▸ Makes it easy to swap components for mocks in tests
14. BASIC DEPENDENCY INJECTION public class Beer { Water water; Barley barley; Hops hops; public Beer(Water water, Barley barley, Hops hops) { this.water = water; this.barley = barley; this.hops = hops; } }
15. DAGGER A Java dependency injection library
16. DAGGER ▸ Define dependencies at compile time to avoid reflection at runtime ▸ Compiler validates modules and injections ▸ Jake Wharton “Architecting Android Applications with Dagger" goo.gl/JIM7KI square.github.io/dagger
17. DAGGER MODULES @Module(injects = {MyActivity.class, MyFragment.class}) public class MyModule { @Provides @Singleton public MyService provideMyService() { return new MyService(); } }
18. DAGGER OBJECT GRAPH public class MyApplication extends Application { private dagger.ObjectGraph objectGraph; @Getter static MyApplication instance; @Override public void onCreate() { super.onCreate(); instance = this; objectGraph = dagger.ObjectGraph.create(new MyModule()); } public void inject(Object dependent) { objectGraph.inject(dependent); } }
19. DAGGER DEPENDENCY INJECTION public class MyFragment extends Fragment { @Inject MyService service; @Override public void onViewCreated(View view, Bundle savedInstanceState) { MyApplication.getInstance().inject(this); service.getMyData(); } }
20. MOCKING & STUBBING
21. MOCKING & STUBBING ▸ Substitute runtime implementation for something that can be predictably tested in isolation ▸ Verify behavior
22. MOCKITO A Java mocking library
23. MOCKITO ▸ Mock/stub dependencies and function return values ▸ Inject mocks to validate behavior in tests ▸ Use included Hamcrest matchers for clear, readable tests code.google.com/p/mockito/
24. USING MOCKITO MyClass mocked = mock(MyClass.class); // code to inject mock & load activity/fragment // ... verify(mocked).getMyData(anyInt(), anyString());
25. UNIT & INTEGRATION TESTS
26. "Tests or it didn't happen."
27. ESPRESSO An Android UI test library
28. ESPRESSO ▸ Handles activity creation & state sync ▸ Simple, concise API ▸ Really fast! code.google.com/p/android-test-kit
29. USING ESPRESSO public class MyActivityTest extends ActivityInstrumentationTestCase2<MyActivity> { public MyActivityTest() { super(MyActivity.class); } @Override protected void setUp() throws Exception { super.setUp(); getActivity(); // trigger activity launch } public void testInvalidEmailShowsError() { onView(withId(R.id.email)).perform(typeText("abc"), closeSoftKeyboard()); onView(withId(R.id.email_sign_in_button)).perform(click()); onView(withId(R.id.email)).check(matches(withError( getActivity().getString(R.string.error_invalid_email)))); } }
30. SAMPLE APPLICATION OVERVIEW ▸ Retrofit API with sample requests ▸ Dagger module ▸ Lombok & Android Studio plugin ▸ Login activity ▸ Activity with list fragment to make API request and display data
31. HABEN SIE FRAGEN?
32. CODE & SLIDES github.com/abdyer/android-test-demo